The HP 6253A Power Supply features constant voltage/current modes with outputs available from 0 to 20 V at 0 to 3 A. Remote sensing. Remote programming. Auto-series/auto-parallel operation. Auto-tracking. Independently adjustable front and rear panel outputs. Voltage mode regulation ±(0.01% + 4 mV). Current mode regulation ±(0.01% + 250 µA). Input is 115 VAC (±10%), 48-440 Hz. Option 011 = Internal Overvoltage Protection Crowbar. Option 040 = Interfacing for Multiprogrammer Operation.